SITE INFORMATION AND CORRESPONDENCE

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Columbo/Toscana - 2 - 26 September 2006 1444 S. Lincoln St., Stockton Maximum groundwater results in 1997 in /L were: Well Screen TPH B T E X MtBE MW-7-S 55-63 100,000 19,000 17,000 2,200 8,000 120 MW-7-D 80-85 10,000 1,300 1,200 220 1,000 <50 1-well screen interval in feet bgs 2—Benzene 3—Toluene 4—Ethylbenzene 5-Xylenes A Cone Penetrometer Survey (CPT) was conducted in December 1997, consisting of three soundings (Figure 2B). Grab groundwater samples were collected at 82, 94, and 106 feet bgs. Maximum results (CPT1-106) were: TPHg, 2,800 pg/L; benzene, 260 pg/L; toluene, 530 pg/L; ethylbenzene, 54 pg/L; and xylenes, 250 pg/L. Besides the quarterly monitoring of the two Texaco wells onsite by TexacoPhillips, no additional work has been completed since 1998 despite repeated written requests by the SJCEHD. In a letter dated 4 August 2005, SJEHD required the submittal by 30 September 2005 of a workplan to delineate the vertical and lateral extent of the petroleum hydrocarbons, and the resumption of quarterly monitoring. On 20 September 2006, Nuel Henderson of SJCEHD and I conducted a site inspection. Mr. Overton, the owner, met us at the property and requested that the approximately twenty rusting drums containing Investigative Derived Waste (IDW, soil or groundwater) be removed. The drums have been sitting at the Site since 1997 and are deteriorating to the point that soil is visible through holes in the drums. Since there are potentially hazardous substances in the soil cuttings or water, there is a risk to individuals from exposure by direct contact, as well as a potential risk that contamination might be released to the unpaved surface by the winter rains, resulting in an unauthorized release to the environment. I have conducted a preliminary case review and agree with the previous directions given by SJCEHD. Therefore, you need to comply with all SJCEHD directives given to date, including but not limited to: • By 22 October 2006, remove all drums containing IDW and properly dispose in the appropriate facility. Metz Bakery (AKA Earthgrains Company) and SECOR are responsible for proper disposal of IDW generated as waste during the investigations of 1996-97. • By 31 October 2006, submit a workplan for an additional investigation to delineate the vertical and lateral extent of the petroleum hydrocarbon release to soil and groundwater. A report of the investigation, due 3 January 2006, shall provide conclusions and recommendations for additional investigation or remediation, if warranted. • Conduct routine quarterly monitoring of all monitoring wells. While nearby sites show a northern groundwater direction, note that three monitoring wells (not two at different depths and lithologic zones) in similar lithology/depths are the minimum number required to triangulate water levels and determine the direction of groundwater movement. Since there may be commingling of petroleum hydrocarbons plumes from nearby sites, establishing the groundwater direction is necessary to understand the